New results on water in bulk, nanoconfined, and biological environments

Water is perhaps die most ubiquitous, and the most essential, of any molecule on earth. Despite decades of research, however, water's puzzling properties are not understood and 63 anomalies that distinguish water front other liquids remain unsolved. We present evidence from experiments and computer simulations supporting the hypothesis that water displays polyamorphism, i.e., water separates into two distinct liquid phases. This concept of a new liquid-liquid critical point is finding application to other liquids as well as water, such as silicon and silica. We also discuss related puzzles, such as the mysterious behavior of water near a biomolecule.